Hi,

i have a '92 twin turbo RX7 (FD3s) and I am having some acceleration issues after the car hits normal opperating temperature. When I step on the gas the engine seems to cut out, backfire and lose all power. The car idles great, it's only when I step on the gas where I encounter the problem. Any help would be greatly appreciated. This one has me stumped.

Thanks

 

Still haven't found what the issue is. Spent the last two weeks going over several hundred posts for a lot of other issues that are simular but not quite the same.

My car starts easy, run's smooth at high idle as it should. Even a few minutes before it's at full operating temp I can press quickly on the throttle and bring the rpms up to 6k. you can hear the blow off valve release preasure as it should.

It's only after the engine warms up that the issue occurrs. I can lightly press on the accelerator up to 6K. But, if I were to give it gas a little quicker it will want to cut out at about 3k.

I've cheched the vac lines etc. The car was running great befor I put in a 3 core rad and a front mounted intercooler, as I would like to keep the engine as cool as possible.

Any help or suggestions would be greatly appreciated.
thanks

 

Mods? Sounds like LIMP mode to me. Like you can slowly get gas it up to higher rpms but if you step on it it will cut out at around 3-4k rpm.

Pull codes and see if you have any faults in the system.

-AzEKnightz

 

Only mods are catback exhaust, HKS air cleaners, HKS blow off valve, Greddy LS front mount intercooler. It has a turbo timer and rev limiter. I've replaced the motor about 1 1\2 years back. Unfortunately I can't read any codes from this car. The reason is I had it improted from Japan and it doesn't have that option.

Your discription on how it's running is very accurate. I tried searching the term limp mode but none of the suggestions helped.

I was thinking of picking up an Apexi power FC. Would you know if this would help correct or diagnois the problem?

The car is running beautifully, other than the drop it power. Only when it's not fully warmed up.
thanks.

 

IIRC limp mode will not allow you to exceed 4k rpms? Regardless of engine temp.

My car had this problem slightly but happened when car was hot or cold.it was causes by a severely out of spec tps. Even to this day my idle is not perfect but driveability is and I don't want to touch it and make it worse.

So I would check tps and grounds maybe?

 

https://www.rx7club.com/3rd-gen-archives-73/there-any-chance-read-ecu-codes-without-ecl-238994/

 

Cool, thanks for the link. I'll try the home made CEL. Hope it works. I've cleaned up all grounds and no change.

 

I had a real similar problem, it ended up being the coolant temp sensor. I tried for weeks to solve it and couldn't, so I bought a PFC and watched the sensor check and the coolant sensor was fine till it warmed then it read open and the car ran like you described. Check the ohms on the coolant sensor, at 20C it should read between 2.2-2.7k-Ohms and at 80C it should be 0.29-0.35. Hope this helps